bug#17926: Menu and tooltip glitches using GTK toolkit

[Robert Parlett <r.parlett@zen.co.uk>]

On 04/07/14 12:07, Jan Djärv wrote:
> 2014-07-04 00:15, Robert Parlett skrev:
>> When I click on a menu - say the Options menu, then cursor down to a 
>> sub-menu
>> - say "Line wrapping in this buffer" - then when the pointer reaches the
>> sub-item, its menu doesn't open.  I then have to move the mouse 
>> slightly, and
>> only then does the menu open.
>
> I tried this on Ubuntu 14.04, with emacs 24.4 candidate and emacs 
> trunk.  They don't exhibit the problem you describe, sub menus are 
> opened at once.
>
>
>> Further, tooltips in a menu sometimes don't
>> appear correctly at first.   They appear clipped and incomplete, but 
>> a further
>> mouse move makes them redraw correctly.
>
> I can't reproduce this either.  In the future, please refrain from 
> reporting two problems in one bug report, make two separate bug 
> reports instead.
>
> Did you starte emacs with -Q?  You do not seem to run vanilla Ubuntu, 
> but rather have another theme/window manager.  Please give the details 
> of that (i.e. desktop environment, theme, window manager).
>
No I didn't try emacs with -Q.  Now that I try that I see that the 
problem is somewhat masked by the blinking cursor.  Normally, I don't 
have a blinking cursor - I have (blink-cursor-mode 0) in my init file.  
When starting with -Q, then the cursor blinks, and the redrawing of the 
blinking cursor obviously also causes the missing menus and half-drawn 
tooltips to be redrawn.  So with -Q, I just see a short - but still 
perceivable - delay before the menus/tooltips are drawn correctly.  If I 
then enter (blink-cursor-mode 0) in the scratch buffer, then I see the 
bug as described originally.

So please try with (blink-cursor-mode 0) and hopefully you will be able 
to reproduce the bug.

I take your point about filing two separate bugs in one report, but the 
missing menu and missing tooltip appear (at least so far as I can see) 
to relate to the same underlying problem, namely a failure to redraw the 
screen correctly.

Regarding the window manager, it is fvwm.  However, I have just tried 
running emacs in Xephyr, without any window manager at all, and the 
problem still occurs.